What are the current theories on the development of a conscious AI?
To answer this question, first we need to know why developing conscious AI is hard. 
The main reason is that there is no mathematically or otherwise rigorous definition of consciousness. 
Sure you have an idea of consciousness as you experience it and we can talk about philosophical zombies but it isn’t a tangible concept that can be broken down and worked on. 
Moreover, the majority of current research in AI is primarily a pragmatic approach in that one is trying to construct a model that can perform well according to some desired cost function. This is a very very big and exciting field and encompasses many research problems and every new finding is based either on mathematical theory or empirical evidence of a new algorithm/model construction/etc. 
Because of this, progress is based on and compared against previous progress as it is the scientific method. 

So to answer your question, no one is trying to actually make a “conscious” AI because we don’t know what that word means yet, however that doesn’t stop people talking about it.